Of course yet I have more food questions?

Yes, you can overcook chicken and lose some of the nutrients. The best way to boil chicken is to put the chicken in the water, bring it to a boil, then reduce the heat and simmer until the chicken is tender and comes apart easily. It really depends on the size of the piece of chicken as to how long it will take. The banana/avocado/peach mixture is fine. Banana and avocado change color when they are exposed to oxygen...they don't look as appetizing, but they taste the same.